This invention relates to closure caps for sealing the mouths of bottles and other containers. It has particular application to the sealing of bottles and other containers against the leakage or spillage of liquid materials during the shipping thereof where vibration frequently causes the closure caps to loosen, and also in the process of removing the closure cap from the mouth of the container involved.
It is especially important to prevent spillage of corrosive materials which can cause damage to the user or to metal or other surfaces upon which such materials may drip during undesired leakage from the container involved. It has been, therefore, proposed to place a secondary seal over the mouths of containers carrying such corrosive materials beneath the usual closure cap which sealingly interlocks with the neck portions of the containers involved when tightened thereon. In such case, the loosening of the closure cap during shipment will not destroy the secondary seal which must be separately removed to gain access to the contents of the container. To remove such a secondary seal, however, adds a hazard to the user or the equipment which may be utilized to severe or pry loose the secondary seal. For example, if the secondary seal is severable diaphragm and it is punctured by a screwdriver or other tool, the portion of the tool which enters the mouth of the container can contact the corrosive material therein and be damaged thereby. In those cases where the secondary seal is a plug or the like which must be manually pried loose from the container, in the process of pulling the sealing member from the container the bottle is often violently shaken resulting in spillage of the container contents onto the user's skin or clothing.
There have been heretofore developed a closure cap and sealing member assembly where, initially at least, the closure cap carries a sealing member, and in the process of securing the closure cap in place the sealing member is automatically pressed into a sealing position within the container mouth involved. In one form of such a closure cap and sealing member assembly, the sealing member is separated or severed from the closure cap when the closure cap is tightened on the container mouth. Such a closure cap and sealing member assembly is disclosed in U.S. Pat. No. 3,425,579 to M. Braun et al. In another form of closure cap and sealing member assembly, the sealing member is finally removed from the container mouth after complete release of the closure cap by pulling on the closure cap to apply sufficient outward force to release the sealing member. Such a closure cap assembly is disclosed in U.S. Pat. No. 3,753,510 which utilizes a bayonet joint interconnection between the closure cap and the container mouth. Both of these closure cap and sealing member assemblies require a substantial separating force when there is a tight fit between the sealing member and container mouth, and the container can be violently shaken during release of the sealing member, causing spillage of the container contents. Also, in the case of the bayonet joint type closure cap, it requires special closure applying equipment to mount the same.
Accordingly, one of the objects of the invention is to provide a sealing closure cap assembly which includes a closure cap which interlocks with the exterior of the mouth of the container involved and which further carries a sealing member which remains in tight sealing relation to the mouth of the bottle at least during initial release of the closure cap, and wherein the sealing member can be released from the mouth of the bottle with a modest force applied in such a way that the bottle will not shake during the release thereof.
A further object of the invention is to provide a closure cap and sealing member assembly as described which can be made at a minimum cost in comparison to more complicated and less effective sealing closure cap assemblies heretofore developed.
Another object of the invention is to provide a closure cap and sealing member assembly as described which can be applied with conventional bottle cap applying equipment.